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arXiv · 0711.0438

Terahertz detection with delta-doped GaAs/AlAs multiple quantum wells

D. Seliuta·B. Cechavicius·J. Kavaliauskas·G. Krivaite·I. Grigelionis·S. Balakauskas·G. Valusis·B. Sherliker·M. P. Halsall·M. Lachab·S. P. Khanna·P. Harrison·E. H. Linfield
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Abstract

The authors demonstrate selective detection of terahertz radiation employing beryllium delta-doped GaAs/AlAs multiple quantum wells. The sensitivity up to 1 V/W within 4.2-7.3 THz range at liquid helium temperatures is reached. The Franz-Keldysh oscillations observed in photo- and electro-reflectance spectra allowed one to estimate built-in electric fields in the structures studied. It was found that the electric field strength in the cap layer region could vary from 10 kV/cm up to 26 kV/cm, depending on the structure design and temperature.

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D. Seliuta, B. Cechavicius, J. Kavaliauskas, G. Krivaite, I. Grigelionis, S. Balakauskas, G. Valusis, B. Sherliker, M. P. Halsall, M. Lachab, S. P. Khanna, P. Harrison, E. H. Linfield. 2007-11-03. Terahertz detection with delta-doped GaAs/AlAs multiple quantum wells. https://arxiv.org/abs/0711.0438

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